merge_arrow_pr.py

#!/usr/bin/env python

#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

# Utility for creating well-formed pull request merges and pushing them to
# Apache.
#   usage: ./apache-pr-merge.py    (see config env vars below)
#
# This utility assumes you already have a local Arrow git clone and that you
# have added remotes corresponding to both (i) the Github Apache Arrow mirror
# and (ii) the apache git repo.

import os
import re
import subprocess
import sys
import requests
import getpass

from six.moves import input
import six

try:
    import jira.client
    JIRA_IMPORTED = True
except ImportError:
    JIRA_IMPORTED = False

# Location of your Arrow git clone
ARROW_HOME = os.path.abspath(__file__).rsplit("/", 2)[0]
PROJECT_NAME = ARROW_HOME.rsplit("/", 1)[1]
print("ARROW_HOME = " + ARROW_HOME)
print("PROJECT_NAME = " + PROJECT_NAME)

# Remote name which points to the Gihub site
PR_REMOTE_NAME = os.environ.get("PR_REMOTE_NAME", "apache-github")
# Remote name which points to Apache git
PUSH_REMOTE_NAME = os.environ.get("PUSH_REMOTE_NAME", "apache")
# ASF JIRA username
JIRA_USERNAME = os.environ.get("JIRA_USERNAME")
# ASF JIRA password
JIRA_PASSWORD = os.environ.get("JIRA_PASSWORD")

GITHUB_BASE = "https://github.com/apache/" + PROJECT_NAME + "/pull"
GITHUB_API_BASE = "https://api.github.com/repos/apache/" + PROJECT_NAME
JIRA_BASE = "https://issues.apache.org/jira/browse"
JIRA_API_BASE = "https://issues.apache.org/jira"
# Prefix added to temporary branches
BRANCH_PREFIX = "PR_TOOL"

os.chdir(ARROW_HOME)


def get_json(url):
    req = requests.get(url)
    return req.json()


def fail(msg):
    print(msg)
    clean_up()
    sys.exit(-1)


def run_cmd(cmd):
    if isinstance(cmd, six.string_types):
        cmd = cmd.split(' ')

    try:
        output = subprocess.check_output(cmd)
    except subprocess.CalledProcessError as e:
        # this avoids hiding the stdout / stderr of failed processes
        print('Command failed: %s' % cmd)
        print('With output:')
        print('--------------')
        print(e.output)
        print('--------------')
        raise e

    if isinstance(output, six.binary_type):
        output = output.decode('utf-8')
    return output


def continue_maybe(prompt):
    result = input("\n%s (y/n): " % prompt)
    if result.lower() != "y":
        fail("Okay, exiting")


original_head = run_cmd("git rev-parse HEAD")[:8]


def clean_up():
    print("Restoring head pointer to %s" % original_head)
    run_cmd("git checkout %s" % original_head)

    branches = run_cmd("git branch").replace(" ", "").split("\n")

    for branch in [x for x in branches if x.startswith(BRANCH_PREFIX)]:
        print("Deleting local branch %s" % branch)
        run_cmd("git branch -D %s" % branch)


# merge the requested PR and return the merge hash
def merge_pr(pr_num, target_ref):
    pr_branch_name = "%s_MERGE_PR_%s" % (BRANCH_PREFIX, pr_num)
    target_branch_name = "%s_MERGE_PR_%s_%s" % (BRANCH_PREFIX, pr_num,
                                                target_ref.upper())
    run_cmd("git fetch %s pull/%s/head:%s" % (PR_REMOTE_NAME, pr_num,
                                              pr_branch_name))
    run_cmd("git fetch %s %s:%s" % (PUSH_REMOTE_NAME, target_ref,
                                    target_branch_name))
    run_cmd("git checkout %s" % target_branch_name)

    had_conflicts = False
    try:
        run_cmd(['git', 'merge', pr_branch_name, '--squash'])
    except Exception as e:
        msg = ("Error merging: %s\nWould you like to "
               "manually fix-up this merge?" % e)
        continue_maybe(msg)
        msg = ("Okay, please fix any conflicts and 'git add' "
               "conflicting files... Finished?")
        continue_maybe(msg)
        had_conflicts = True

    commit_authors = run_cmd(['git', 'log', 'HEAD..%s' % pr_branch_name,
                             '--pretty=format:%an <%ae>']).split("\n")
    distinct_authors = sorted(set(commit_authors),
                              key=lambda x: commit_authors.count(x),
                              reverse=True)
    primary_author = distinct_authors[0]
    commits = run_cmd(['git', 'log', 'HEAD..%s' % pr_branch_name,
                      '--pretty=format:%h [%an] %s']).split("\n\n")

    merge_message_flags = []

    merge_message_flags += ["-m", title]
    if body is not None:
        merge_message_flags += ["-m", body]

    authors = "\n".join(["Author: %s" % a for a in distinct_authors])

    merge_message_flags += ["-m", authors]

    if had_conflicts:
        committer_name = run_cmd("git config --get user.name").strip()
        committer_email = run_cmd("git config --get user.email").strip()
        message = ("This patch had conflicts when merged, "
                   "resolved by\nCommitter: %s <%s>" %
                   (committer_name, committer_email))
        merge_message_flags += ["-m", message]

    # The string "Closes #%s" string is required for GitHub to correctly close
    # the PR
    merge_message_flags += [
        "-m",
        "Closes #%s from %s and squashes the following commits:"
        % (pr_num, pr_repo_desc)]
    for c in commits:
        merge_message_flags += ["-m", c]

    run_cmd(['git', 'commit',
             '--no-verify',  # do not run commit hooks
             '--author="%s"' % primary_author] +
            merge_message_flags)

    continue_maybe("Merge complete (local ref %s). Push to %s?" % (
        target_branch_name, PUSH_REMOTE_NAME))

    try:
        run_cmd('git push %s %s:%s' % (PUSH_REMOTE_NAME, target_branch_name,
                                       target_ref))
    except Exception as e:
        clean_up()
        fail("Exception while pushing: %s" % e)

    merge_hash = run_cmd("git rev-parse %s" % target_branch_name)[:8]
    clean_up()
    print("Pull request #%s merged!" % pr_num)
    print("Merge hash: %s" % merge_hash)
    return merge_hash


def fix_version_from_branch(branch, versions):
    # Note: Assumes this is a sorted (newest->oldest) list of un-released
    # versions
    if branch == "master":
        return versions[0]
    else:
        branch_ver = branch.replace("branch-", "")
        return [x for x in versions if x.name.startswith(branch_ver)][-1]


def exctract_jira_id(title):
    m = re.search(r'^(ARROW-[0-9]+)\b.*$', title)
    if m and m.groups > 0:
        return m.group(1)
    else:
        fail("PR title should be prefixed by a jira id "
             "\"ARROW-XXX: ...\", found: \"%s\"" % title)


def check_jira(title):
    jira_id = exctract_jira_id(title)
    asf_jira = jira.client.JIRA({'server': JIRA_API_BASE},
                                basic_auth=(JIRA_USERNAME, JIRA_PASSWORD))
    try:
        asf_jira.issue(jira_id)
    except Exception as e:
        fail("ASF JIRA could not find %s\n%s" % (jira_id, e))


def resolve_jira(title, merge_branches, comment):
    asf_jira = jira.client.JIRA({'server': JIRA_API_BASE},
                                basic_auth=(JIRA_USERNAME, JIRA_PASSWORD))

    default_jira_id = exctract_jira_id(title)

    jira_id = input("Enter a JIRA id [%s]: " % default_jira_id)
    if jira_id == "":
        jira_id = default_jira_id

    try:
        issue = asf_jira.issue(jira_id)
    except Exception as e:
        fail("ASF JIRA could not find %s\n%s" % (jira_id, e))

    cur_status = issue.fields.status.name
    cur_summary = issue.fields.summary
    cur_assignee = issue.fields.assignee
    if cur_assignee is None:
        cur_assignee = "NOT ASSIGNED!!!"
    else:
        cur_assignee = cur_assignee.displayName

    if cur_status == "Resolved" or cur_status == "Closed":
        fail("JIRA issue %s already has status '%s'" % (jira_id, cur_status))
    print("=== JIRA %s ===" % jira_id)
    print("summary\t\t%s\nassignee\t%s\nstatus\t\t%s\nurl\t\t%s/%sf\n"
          % (cur_summary, cur_assignee, cur_status, JIRA_BASE, jira_id))

    resolve = filter(lambda a: a['name'] == "Resolve Issue",
                     asf_jira.transitions(jira_id))[0]
    asf_jira.transition_issue(jira_id, resolve["id"], comment=comment)

    print("Succesfully resolved %s!" % (jira_id))


if not JIRA_USERNAME:
    JIRA_USERNAME = input("Env JIRA_USERNAME not set, "
                          "please enter your JIRA username:")

if not JIRA_PASSWORD:
    JIRA_PASSWORD = getpass.getpass("Env JIRA_PASSWORD not set, please enter "
                                    "your JIRA password:")

branches = get_json("%s/branches" % GITHUB_API_BASE)
branch_names = [x['name'] for x in branches if x['name'].startswith('branch-')]

# Assumes branch names can be sorted lexicographically
# Julien: I commented this out as we don't have any "branch-*" branch yet
# latest_branch = sorted(branch_names, reverse=True)[0]

pr_num = input("Which pull request would you like to merge? (e.g. 34): ")
pr = get_json("%s/pulls/%s" % (GITHUB_API_BASE, pr_num))

url = pr["url"]
title = pr["title"]
check_jira(title)
body = pr["body"]
target_ref = pr["base"]["ref"]
user_login = pr["user"]["login"]
base_ref = pr["head"]["ref"]
pr_repo_desc = "%s/%s" % (user_login, base_ref)

if pr["merged"] is True:
    print("Pull request %s has already been merged, "
          "assuming you want to backport" % pr_num)
    merge_commit_desc = run_cmd([
        'git', 'log', '--merges', '--first-parent',
        '--grep=pull request #%s' % pr_num, '--oneline']).split("\n")[0]
    if merge_commit_desc == "":
        fail("Couldn't find any merge commit for #%s, "
             "you may need to update HEAD." % pr_num)

    merge_hash = merge_commit_desc[:7]
    message = merge_commit_desc[8:]

    print("Found: %s" % message)
    sys.exit(0)

if not bool(pr["mergeable"]):
    msg = ("Pull request %s is not mergeable in its current form.\n"
           % pr_num + "Continue? (experts only!)")
    continue_maybe(msg)

print("\n=== Pull Request #%s ===" % pr_num)
print("title\t%s\nsource\t%s\ntarget\t%s\nurl\t%s"
      % (title, pr_repo_desc, target_ref, url))
continue_maybe("Proceed with merging pull request #%s?" % pr_num)

merged_refs = [target_ref]

merge_hash = merge_pr(pr_num, target_ref)

if JIRA_IMPORTED:
    continue_maybe("Would you like to update the associated JIRA?")
    jira_comment = ("Issue resolved by pull request %s\n[%s/%s]"
                    % (pr_num, GITHUB_BASE, pr_num))
    resolve_jira(title, merged_refs, jira_comment)
else:
    print("Could not find jira-python library. "
          "Run 'sudo pip install jira-python' to install.")
    print("Exiting without trying to close the associated JIRA.")